Delayed action fuze



United States Patent O 3,320,891 DELAYED ACTION FUZE Donald lE. Holmes,Greenville, Ohio, assignor to Avco Corporation, Riclmond, End., acorporation of Dela- Ware Filed Oct. 4, 1965, Ser. No. 492,683 Claims.(CI. 102-82) ABSTRACT OF THE DISCLOSURE This fnze has a generallycup-shape stator and a rotor, formed to define a raceway. Carried by thestator, and disposed in this raceway is a pliable tube. Bearings aredisposed in the raceway and urged against this tube by the rotor. Therotor is unlocked from the stator by centrfugal force and the rotormoves clockwise into arming position, the motion being delayed by thesqueezing and pumping action of the ball *bearings, acting on the tube.

The present invention relates to timing devices for fuzes, and itsprovides an improved means for delaying the initiation of a fuzefunction until a predetermined time following an initial event.

The principal object of the invention is to provide a delaye d firing orarming fuze which is reliable and uniform in performancecharacteristics.

For a better Understanding of the invention, together with other andfurther objects, advantages, and capabilities thereof, reference is madeto the following description of the appended drawings, in which:

FIG. l is a plan View of a delayed firing fuze in accordance with theinvention;

FIG. 2 is a sectional View of the improved fuze as taken along thesection line 2--2 of FIG. 1 and looking in the direction of the arrows;and

FIGS. 3 and 4 are fragmentary sectional views showing alternate rollerelements for incorporation in the improved fuze.

The fuze herein shown comprises, among other elements hereinafterdescribed, a stator which consists of two members designated and 11.tator member 10 is generally cup-shaped in contour. An annular retaininggroove is located on the inner wall. In the groove is positioned apliable tire-like tube 12 which functions as the principal time-delayelement, as hereinafter described. The closed portion of member 10` isformed with a port 13 through which the firing train is propagated.Further formed in the closed portion of member 10 is a hole 15 whichserves to release the striker locking ball 28 when the rotor has movedto the firing position. The stator member 10 and the rotor are shaped toprovide an annular ndentation in which there is disposed a spitallyWound power spring which in installed and preloaded so as to result inclockwise rotation of the rotor 20' with respect to the stator 10, asviewed in FlG. 1, This spring is identified as 16.

Referring now to the stator member 11, its general contour is that of acircular cap for the principal stator body member 10. The stator member11 has an integral cylindrical extension 9 which serves as a shaft onwhich the rotor 20` rotates. The extension contains a cylindrical recesspositioned normal to the principal axis of the extension. The recesscontains a primer 19, the first explosive element in the firing train.

Coming now to a description of the rotor 20, it is generally cylindricalin configuration and mounted on the cylindrical extension 9 for rotationrelative to the stator. Three 90-degree displaced wells 21, 22, and 23are formed in the rotor. Well 21 provides a cylinder for the pisten-likestriker 18. In wells 22 and 23` there are mounted springs 24 and 25,respectively, which urge ontwardly the cylindrical bearings 26 and 27,thereby depressing the pliable tube 12. The -bearings are in a racewaydefined by the rotor and stator.

In FIGS. 3 and 4 there are shown alternate forms of hearing 27' and tube12', the essential difference between the FIGS. 3 and 4 embodimentsbeing that in FIG. 3 the hearing is spherical and is urged diagonallyand radially by the spring 25, whereas in FIG. 4 the hearing 27' is ofthe roller type and is urged radially outward.

FIG. 1 illustrates the conditions which exist when the fuze is inunarmed condition. As the device containing the fuze is fired and spinsthe detent pin 30 moves radially outwardly under centrifugal forces anddisengages from the notch 31 in the stator portion 9, permitting therotor to turn. It will be understood that the pin moves outwardly inwell 33 against the bias of the spring 32 which normally keeps pin 30pushed inwar-dly.

The rotor 20, containing the striker 18, rotates clockwise throughdegrees and aligns the striker 18 With the primer 19. As alignment isreached, the striker locking -ball 28 drops into the hole 15, releasingthe springloaded striker 13 to impact the primer 19, thus initiating thefiring train which passes through the aperture 13 to successiveexplosive elements.

This necessary rotation of the rotor from the FIG. 1 position is delayedor clocked by reason of the fluid in tube 12 being displaced throughorifice 7 by the squeezing and pumping action of rollers 26 and 27. Thetime of this delay s a function of the rotational force on rotor 20 dueto the motor spring 16, the effective fluid orifice provided by theelements 12 and 26, 27, the orifice 7, the viscosity of the fluid inelement 12, and the initial and Operating fluid pressures.

The principles of this invention stated broadly are:

(a) One rotatable member, i.e., rotor element 20 must travel a certainnumber of angular degrees With respect to a stator 10 to unlock a gateand perform a desired -delayed arming function;

(b) The movement of this rotor 20 is impeded by at least one ball 26and/or 27 or roller traveling on or in a pliable track 12 wherein aViscous fluid must be displaced rearward through the eifective orificeformed in the fluid contaner 12 by depression of this track by the ballto allow movement (orifice 7 is an optional feature), and

(c) The restrainng gate is unlocked at the end of the damped rotortravel and the desired arming action is promoted after the projectile isa safe distance from the gun muzzle.

The fuze and initially positioned FIGS. l-2 device are mounted in a spirstabilized projectile. The stator 10 is integral with the projectilebody and rotates with it. The energy of the spring 16 is expended in theforced fluid -displacement as the balls depressing the fluid sac 12travel to unlock the safety and arm the fuze.

These rotor and stator functions may be reversed in a manner such thatthe fluid sac 12 is carried on the rotor.

Principles of this invention are adaptable to various design treatment.Almost an noncornpressible fluid may be used from water to mercury inthe pliant sac 12. The choice will be dictated largely by the particularconstruction and performance desired. The rotor rotation may range froma few degrees of arc to essentially full 360 degrees.

From the foregoing description it will be understood that the inventionprovides:

In a fuze of the type comprising a striker 18 and relatively angularlymovable rotor 20 and stator 10 members for bringing the striker intoalignment with a firing train 19, the combination of: a flexible tube 12containing a hydraulic fluid carried -by one of said members, and atleast one roller mounted in and urged from the other member to constrictsaid tu be and to propel fluid through an orifice in order to delayrotation between said members.

While there have been shown and described what are vatepresentconsidered to -be the preferred embodirnents of the invention, it willbe understood by those skilled in the art that various modifications andchange-s may be made therein without departing from the true scope ofthe invention as defined by the appended claims.

I claim:

1. In a fuze of the type comprising a striker and rela- 'tivelyangularly movable rotor and stator members for bringing the striker intoalignment with a firing train, the combintion of:

a fiexible tube containing a hydraulic fluid carried by one of saidmembers, said members defining a raceway, and roller means disposed insaid raceway and urged from the other member to constrict said tube topropel fluid through -an orifice in order to regulate rotation betweensaid members. 2. In a fuze, the com-bination of: a stator; a rotor; astriker carried :by said rotor; a firing train including a primercarried by the stator; a flexible tube containing a hydraulic fluidcarried 'by said stator;

and at least one roller disposed between said rotor and stator forconstricting said tube to provide an effective orifiee and forpropelling fluid through said orifice in order to delay rotation of saidrotor as it turns to align said striker with said primer.

3. In a fuze, the combination in accordance With claim 2 in which thestriker is mounted for radial movement relative to the rotor when thestriker is released, and including means for restrainng the strker untilit is aligned with the primer.

4. The combination in accordance with claim 3 and including spring meansfor imparting torque to the rotor, and means normally preventingrotation of the rotor but responsive to the development of centrifugalforces to permit such rotation.

5. The combination in accordance with claim 4 in which a section of therotor is formed With a fixed orifice.

References Cited by the Examiner UNITED STATES PATENTS 1,142,375 6/1915Smith 102-82 2,893,322 7/1959 Leroy 102-78 X 2,977,883 4/1961 Czajkowski102-79 SAMUEL FEINBERG, Primary Examier.

G. H. GLANZMAN, Assistant Examiner.

1. IN A FUZE OF THE TYPE COMPRISING A STRIKER AND RELATIVELY ANGULARLYMOVABLE ROTOR AND STATOR MEMBERS FOR BRINGING THE STRIKER INTO ALIGNMENTWITH A FIRING TRAIN, THE COMBINATION OF: A FLEXIBLE TUBE CONTAINING AHYDRAULIC FLUID CARRIED BY ONE OF SAID MEMBERS, SAID MEMBERS DEFINING ARACEWAY, AND ROLLER MEANS DISPOSED IN SAID RACEWAY AND URGED FROM THEOTHER MEMBER TO CONSTRICT SAID TUBE TO PROPEL FLUID THROUGH AN ORIFICEIN ORDER TO REGULATE ROTATION BETWEEN SAID MEMBERS.